/*-----------------------------------------------------------------------*/
/* MMC/SDSC/SDHC (in SPI0_SD mode) control module  (C)ChaN, 2007             */
/*-----------------------------------------------------------------------*/
/* Only rcvr_spi(), xmit_spi(), disk_timerproc() and some macros are     */
/* platform dependent.                                                   */
/*Code Modified by Glen Rhodes and Akmal Mohammed on 2/21/2008 for the use*/
/*in a senior design project using the Freescale MC9S12E128/256          */
/*-----------------------------------------------------------------------*/


//#include <mc9s12dp512.h>     /* derivative information */
#include "IO_Map.h"
#include "diskio.h"
#include "SCI.h"
#include "SPI0_SD.h"
#include "SD_CS.h"

/* MMC/SD command (in SPI0_SD) */
#define CMD0	(0x40+0)	/* GO_IDLE_STATE */
#define CMD1	(0x40+1)	/* SEND_OP_COND */
#define	ACMD41	(0xC0+41)	/* SEND_OP_COND (SDC) */
#define CMD8	(0x40+8)	/* SEND_IF_COND */
#define CMD9	(0x40+9)	/* SEND_CSD */
#define CMD10	(0x40+10)	/* SEND_CID */
#define CMD12	(0x40+12)	/* STOP_TRANSMISSION */
#define ACMD13	(0xC0+13)	/* SD_STATUS (SDC) */
#define CMD16	(0x40+16)	/* SET_BLOCKLEN */
#define CMD17	(0x40+17)	/* READ_SINGLE_BLOCK */
#define CMD18	(0x40+18)	/* READ_MULTIPLE_BLOCK */
#define CMD23	(0x40+23)	/* SET_BLOCK_COUNT */
#define	ACMD23	(0xC0+23)	/* SET_WR_BLK_ERASE_COUNT (SDC) */
#define CMD24	(0x40+24)	/* WRITE_BLOCK */
#define CMD25	(0x40+25)	/* WRITE_MULTIPLE_BLOCK */
#define CMD41	(0x40+41)	/* SEND_OP_COND (ACMD) */
#define CMD55	(0x40+55)	/* APP_CMD */
#define CMD58	(0x40+58)	/* READ_OCR */


/* Control signals (Platform dependent) */
//Dont Need these defines because we implement this in spi.c
//#define MMCLK		IO.PDR5.BIT.B0	/* MMC SCLK */
//#define MMDI		IO.PDR5.BIT.B1	/* MMC DI */
//#define MMDO		IO.PDR5.BIT.B2	/* MMC DO */
//#define	MMCS		IO.PDR5.BIT.B3	/* MMC CS */	 

//call SPI0_SD functions
#define SELECT()	SD_CS_ClrVal()		/* MMC CS = L */
#define	DESELECT() SD_CS_SetVal()		/* MMC CS = H */





/*--------------------------------------------------------------------------

   Module Private Functions

---------------------------------------------------------------------------*/
volatile
DSTATUS Stat = STA_NOINIT;	/* Disk status */

volatile
BYTE Timer1, Timer2;	/* 100Hz decrement timer */

static
BYTE CardType;			/* b0:MMC, b1:SDv1, b2:SDv2, b3:Block addressing */




/*-----------------------------------------------------------------------*/
/* Transmit a byte to MMC via SPI0_SD  (Platform dependent)                  */
/*-----------------------------------------------------------------------*/

static
void xmit_spi (BYTE dat)
{
   while(SPI0_SD_SendChar(dat)==ERR_TXFULL){
   }

}



/*-----------------------------------------------------------------------*/
/* Receive a byte from MMC via SPI0_SD (Platform dependent)                  */
/*-----------------------------------------------------------------------*/

static
BYTE rcvr_spi (void)
{  BYTE temp;
	 while(SPI0_SD_SendChar(0xFF)==ERR_TXFULL){
   } 
   
   while(SPI0_SD_RecvChar(&temp)==  ERR_RXEMPTY){
   }
   
   return temp;                            
}



/*-----------------------------------------------------------------------*/
/* Wait for card ready                                                   */
/*-----------------------------------------------------------------------*/

static
BYTE wait_ready (void)
{
	BYTE res;

	Timer2 = 500;			/* Wait for ready in timeout of 500ms */
	rcvr_spi();
	do 
		res = rcvr_spi(); 
	while ((res != 0xFF) && Timer2);    //akmal changed this
	 //	SCI_SendStr("result of cmd: ");
////	SCI_SendNum(res);
//	SCI_SendChar('\n');
	return res;
}



/*-----------------------------------------------------------------------*/
/* Deselect the card and release SPI0_SD bus                                 */
/*-----------------------------------------------------------------------*/

static
void release_spi (void)
{
	DESELECT();
	rcvr_spi();//why does this line exist? -LMS
}



/*-----------------------------------------------------------------------*/
/* Power Control  (Platform dependent)                                   */
/*-----------------------------------------------------------------------*/
/* When the target system does not support socket power control, there   */
/* is nothing to do in these functions and chk_power always returns 1.   */

static
void power_on (void)
{
//	IO.PUCR5.BYTE = 0x30;		/* Enable pull-up for socket contacts */
//	IO.PDR5.BYTE = 0x00;		/* Power ON */
//	IO.PCR5 = 0x80;
//	for (Timer1 = 2; Timer1; );	/* Wait for 20ms */
//	IO.PDR5.BYTE = 0x0E;		/* Enable Driver */
//	IO.PCR5 = 0x8B;
//	for (Timer1 = 1; Timer1; );	/* Wait for 10ms */
}
 

static
void power_off (void)
{
//	SELECT();				/* Wait for card ready */
//	wait_ready();
//	DESELECT();
//	rcvr_spi();

//	IO.PDR5.BYTE = 0x00;	/* Disable driver */
//	IO.PCR5 = 0x80;
//	IO.PDR5.BYTE = 0x80;	/* Power OFF */

//	Stat |= STA_NOINIT;		/* Set STA_NOINIT */
}



/*-----------------------------------------------------------------------*/
/* Receive a data packet from MMC                                        */
/*-----------------------------------------------------------------------*/

static
BOOL rcvr_datablock (
	BYTE *buff,			/* Data buffer to store received data */
	UINT btr			/* Byte count (must be even number) */
)
{
	BYTE token;


	Timer1 = 10;
	do {							/* Wait for data packet in timeout of 100ms */
		token = rcvr_spi();
	} while ((token == 0xFF) && Timer1);  //akmal changed this
	if(token != 0xFE) return FALSE;	/* If not valid data token, retutn with error */

	do {							/* Receive the data block into buffer */
		*buff++ = rcvr_spi();
		*buff++ = rcvr_spi();
	} while (btr -= 2);
	rcvr_spi();						/* Discard CRC */
	rcvr_spi();

	return TRUE;					/* Return with success */
}



/*-----------------------------------------------------------------------*/
/* Send a data packet to MMC                                             */
/*-----------------------------------------------------------------------*/

#if _READONLY == 0
static
BOOL xmit_datablock (
	const BYTE *buff,		/* 512 byte data block to be transmitted */
	BYTE token			/* Data/Stop token */
)
{
	BYTE resp;
	UINT bc = 512;


	if (wait_ready() != 0xFF) return FALSE;

	xmit_spi(token);			/* Xmit data token */
	if (token != 0xFD) {	/* Is data token */
		do {						/* Xmit the 512 byte data block to MMC */
			xmit_spi(*buff++);
			xmit_spi(*buff++);
		} while (bc -= 2);
		xmit_spi(0xFF);				/* CRC (Dummy) */
		xmit_spi(0xFF);
		resp = rcvr_spi();			/* Receive data response */
		if ((resp & 0x1F) != 0x05)	/* If not accepted, return with error */
			return FALSE;
	}

	return TRUE;
}
#endif	/* _READONLY */




/*-----------------------------------------------------------------------*/
/* Send a command packet to MMC                                          */
/*-----------------------------------------------------------------------*/

static
BYTE send_cmd (
	BYTE cmd,		/* Command byte */
	DWORD arg		/* Argument */
)
{
	BYTE n, res;
	short run;


	if (cmd & 0x80) {	/* ACMD<n> is the command sequense of CMD55-CMD<n> */
		cmd &= 0x7F;
		res = send_cmd(CMD55, 0);
		if (res > 1) return res;
	}

	/* Select the card and wait for ready */
	DESELECT();
	SELECT();
 
	if (wait_ready() != 0xFF) return 0xFF;
	/* Send command packet */
	xmit_spi(cmd);						/* Start + Command index */
	xmit_spi((BYTE)(arg >> 24));		/* Argument[31..24] */
	xmit_spi((BYTE)(arg >> 16));		/* Argument[23..16] */
	xmit_spi((BYTE)(arg >> 8));			/* Argument[15..8] */
	xmit_spi((BYTE)arg);				/* Argument[7..0] */
	n = 0x01;							/* Dummy CRC + Stop */
	if (cmd == CMD0) n = 0x95;			/* Valid CRC for CMD0(0) */
	if (cmd == CMD8) n = 0x87;			/* Valid CRC for CMD8(0x1AA) */
	xmit_spi(n);

	/* Receive command response */
	if (cmd == CMD12) rcvr_spi();		/* Skip a stuff byte when stop reading */
	n = 10;								/* Wait for a valid response in timeout of 10 attempts */
	do
		res = rcvr_spi();
	while ((res == 0xFF) && --n);
 //  	SCI_SendStr("result of cmd: ");
	//SCI_SendNum(res);
//	SCI_SendChar('\n');
 for(run=0;run<200;run++){
			    asm nop
			   }

	return res;			/* Return with the response value */
}



/*--------------------------------------------------------------------------

   Public Functions

---------------------------------------------------------------------------*/


/*-----------------------------------------------------------------------*/
/* Initialize Disk Drive                                                 */
/*-----------------------------------------------------------------------*/

DSTATUS disk_initialize (
	BYTE drv		/* Physical drive number (0) */
)
{
	BYTE n, ty, cmd, ocr[4],retry, temp;
	retry = 2;
 
   
	do{
  #if DEBUG_SCI   
  SCI_SendStr("Starting Init\n\r"); //*********    
  #endif
    
    
	  if (drv) return STA_NOINIT;			/* Supports only single drive */
	  if (Stat & STA_NODISK) return Stat;	/* No card in the socket */
  
    power_on();							/* Force socket power on */
	  for (n = 10; n; n--) rcvr_spi();	/* 80 dummy clocks */
 
	  ty = 0;
	
	  
	  if (send_cmd(CMD0, 0) == 1) {			/* Enter Idle state */
    
      
		  Timer1 = 100;						/* Initialization timeout of 1000 msec */
		  if (send_cmd(CMD8, 0x1AA) == 1) {	/* SDHC */
		    //   SCI_SendStr("thinks its SDHC\n\r");	 //*********
			  for (n = 1; n < 4; n++) ocr[n] = rcvr_spi();		/* Get trailing return value of R7 resp */
			  if (ocr[2] == 0x01 && ocr[3] == 0xAA) {				/* The card can work at vdd range of 2.7-3.6V */
				    
				  while (Timer1 && send_cmd(ACMD41, 1UL << 30)){
				    
				  }/* Wait for leaving idle state (ACMD41 with HCS bit) */
				  if (Timer1 && send_cmd(CMD58, 0) == 0) {		/* Check CCS bit in the OCR */
				    
					  for (n = 0; n < 4; n++) ocr[n] = rcvr_spi();
					  ty = (ocr[0] & 0x40) ? 12 : 4;
				  }
			  }
		  } else {							/* SDSC or MMC */
		   
			  if (send_cmd(ACMD41, 0) <= 1) 	{
				  ty = 2; cmd = ACMD41;	/* SDSC */
			  //	SCI_SendStr("Thinks its an SD card\n\r");	 //*********
			  } else {
				  ty = 1; cmd = CMD1;		/* MMC */
			  }
			 
			  Timer1 = 100;
			  temp =0;
			  while (Timer1 && send_cmd(cmd, 0)){
			           
			                temp ++;
			    }/* Wait for leaving idle state */
		
			  if (!Timer1 || send_cmd(CMD16, 512) != 0)	/* Set R/W block length to 512 */
			  { 	
			    
			    ty = 0;
			  }
		  }
	  }
	  CardType = ty;
  	release_spi();

	  if (ty) {			/* Initialization succeded */
		  Stat &= ~STA_NOINIT;		/* Clear STA_NOINIT */
		  retry=0;
	  } else {			/* Initialization failed */
	    retry--;
	  }
  } while(retry);
   #if DEBUG_SCI  
  SCI_SendStr("leaving init\n");
  SCI_SendNum(Stat);
  SCI_SendStr("\n");
  #endif
	  return Stat;
}



/*-----------------------------------------------------------------------*/
/* Get Disk Status                                                       */
/*-----------------------------------------------------------------------*/

DSTATUS disk_status (
	BYTE drv			/* Drive number (0) */
)
{
	return (drv) ? STA_NODISK : Stat;
}



/*-----------------------------------------------------------------------*/
/* Read Sector(s)                                                        */
/*-----------------------------------------------------------------------*/

DRESULT disk_read (
	BYTE drv,			/* Physical drive nmuber (0) */
	BYTE *buff,			/* Pointer to the data buffer to store read data */
	DWORD sector,		/* Start sector number (LBA) */
	BYTE count			/* Sector count (1..255) */
)
{


	if (drv || !count) return RES_PARERR;
	if (Stat & STA_NOINIT) return RES_NOTRDY;

	if (!(CardType & 8)) sector *= 512;	/* Convert to byte address if needed */

	if (count == 1) {	/* Single block read */
		if ((send_cmd(CMD17, sector) == 0)	/* READ_SINGLE_BLOCK */
			&& rcvr_datablock(buff, 512))
			count = 0;
	}
	else {				/* Multiple block read */
		if (send_cmd(CMD18, sector) == 0) {	/* READ_MULTIPLE_BLOCK */
			do {
				if (!rcvr_datablock(buff, 512)) break;
				buff += 512;
			} while (--count);
			send_cmd(CMD12, 0);				/* STOP_TRANSMISSION */
		}
	}
	release_spi();
 
	return count ? RES_ERROR : RES_OK;
}



/*-----------------------------------------------------------------------*/
/* Write Sector(s)                                                       */
/*-----------------------------------------------------------------------*/


#if _READONLY == 0
DRESULT disk_write (
	BYTE drv,			/* Physical drive nmuber (0) */
	const BYTE *buff,	/* Pointer to the data to be written */
	DWORD sector,		/* Start sector number (LBA) */
	BYTE count			/* Sector count (1..255) */
)
{
	if (drv || !count) return RES_PARERR;
	if (Stat & STA_NOINIT) return RES_NOTRDY;
	if (Stat & STA_PROTECT) return RES_WRPRT;

	if (!(CardType & CT_BLOCK)) sector *= 512;	/* Convert to byte address if needed */

	if (count == 1) {	/* Single block write */
		if ((send_cmd(CMD24, sector) == 0)	/* WRITE_BLOCK */
			&& xmit_datablock(buff, 0xFE))
			count = 0;
	}
	else {				/* Multiple block write */
		if (CardType & CT_SDC) send_cmd(ACMD23, count);
		if (send_cmd(CMD25, sector) == 0) {	/* WRITE_MULTIPLE_BLOCK */
			do {
				if (!xmit_datablock(buff, 0xFC)) break;
				buff += 512;
			} while (--count);
			if (!xmit_datablock(0, 0xFD))	/* STOP_TRAN token */
				count = 1;
		}
	}
	release_spi();

	return count ? RES_ERROR : RES_OK;
}
#endif /* _READONLY */
/*-----------------------------------------------------------------------*/
/* Miscellaneous Functions                                               */
/*-----------------------------------------------------------------------*/
DRESULT disk_ioctl (
	BYTE drv,		/* Physical drive number (0) */
	BYTE ctrl,		/* Control code */
	void *buff		/* Buffer to send/receive data block */
)
{
	DRESULT res;
	BYTE n, csd[16], *ptr = buff;
	DWORD csize;


	if (drv) return RES_PARERR;
	if (Stat & STA_NOINIT) return RES_NOTRDY;

	res = RES_ERROR;
	switch (ctrl) {
		case CTRL_SYNC :	/* Flush dirty buffer if present */
			SELECT();
			if (wait_ready() == 0xFF)
				res = RES_OK;
			break;

		case GET_SECTOR_COUNT :	/* Get number of sectors on the disk (WORD) */
			if ((send_cmd(CMD9, 0) == 0) && rcvr_datablock(csd, 16)) {
				if ((csd[0] >> 6) == 1) {	/* SDC ver 2.00 */
					csize = csd[9] + ((WORD)csd[8] << 8) + 1;
					*(DWORD*)buff = (DWORD)csize << 10;
				} else {					/* MMC or SDC ver 1.XX */
					n = (csd[5] & 15) + ((csd[10] & 128) >> 7) + ((csd[9] & 3) << 1) + 2;
					csize = (csd[8] >> 6) + ((WORD)csd[7] << 2) + ((WORD)(csd[6] & 3) << 10) + 1;
					*(DWORD*)buff = (DWORD)csize << (n - 9);
				}
				res = RES_OK;
			}
			break;

		case GET_SECTOR_SIZE :	/* Get sectors on the disk (WORD) */
			*(WORD*)buff = 512;
			res = RES_OK;
			break;

		case GET_BLOCK_SIZE :	/* Get erase block size in unit of sectors (DWORD) */
			if (CardType & CT_SD2) {	/* SDC ver 2.00 */
				if (send_cmd(ACMD13, 0) == 0) {		/* Read SD status */
					rcvr_spi();
					if (rcvr_datablock(csd, 16)) {				/* Read partial block */
						for (n = 64 - 16; n; n--) rcvr_spi();	/* Purge trailing data */
						*(DWORD*)buff = 16UL << (csd[10] >> 4);
						res = RES_OK;
					}
				}
			} else {					/* SDC ver 1.XX or MMC */
				if ((send_cmd(CMD9, 0) == 0) && rcvr_datablock(csd, 16)) {	/* Read CSD */
					if (CardType & CT_SD1) {		/* SDC ver 1.XX */
						*(DWORD*)buff = (((csd[10] & 63) << 1) + ((WORD)(csd[11] & 128) >> 7) + 1) << ((csd[13] >> 6) - 1);
					} else {					/* MMC */
						*(DWORD*)buff = ((WORD)((csd[10] & 124) >> 2) + 1) * (((csd[11] & 3) << 3) + ((csd[11] & 224) >> 5) + 1);
					}
					res = RES_OK;
				}
			}
			break;

		case MMC_GET_TYPE :		/* Get card type flags (1 byte) */
			*ptr = CardType;
			res = RES_OK;
			break;

		case MMC_GET_CSD :	/* Receive CSD as a data block (16 bytes) */
			if ((send_cmd(CMD9, 0) == 0)	/* READ_CSD */
				&& rcvr_datablock(buff, 16))
				res = RES_OK;
			break;

		case MMC_GET_CID :	/* Receive CID as a data block (16 bytes) */
			if ((send_cmd(CMD10, 0) == 0)	/* READ_CID */
				&& rcvr_datablock(buff, 16))
				res = RES_OK;
			break;

		case MMC_GET_OCR :	/* Receive OCR as an R3 resp (4 bytes) */
			if (send_cmd(CMD58, 0) == 0) {	/* READ_OCR */
				for (n = 0; n < 4; n++)
					*((BYTE*)buff+n) = rcvr_spi();
				res = RES_OK;
			}
			break;

		case MMC_GET_SDSTAT :	/* Receive SD statsu as a data block (64 bytes) */
			if (send_cmd(ACMD13, 0) == 0) {	/* SD_STATUS */
				rcvr_spi();
				if (rcvr_datablock(buff, 64))
					res = RES_OK;
			}
			break;

		default:
			res = RES_PARERR;
	}

	release_spi();

	return res;
}

